Last week Philip Hallstrom posted Ruby in a Nutshell... offering a quick visual comparison of four of O'Reilly's books and dramatically illustrating how much simpler Ruby is than Java. Inspired by this, I just spent a few minutes poking around the O'Reilly web site to construct what we might call the "Nutshell Index": how many pages it takes to cover the essentials of a language or technology. Without further ado: 

 224 Ruby
 240 UML
 352 Rails
 384 PHP
 576 MySQL
 576 Cocoa
 592 SQL
 624 C
 720 XML
 742 Python
 768 Perl
 768 VB.NET
 816 C++
 832 Web design
 944 Linux
1046 C#
1264 Java
And yes, I know this has no statistical validity at all - likely it represents more the coverage depth decisions made by individual authors and editors more than anything else. Still fun.